Antibiotic use during birth affects infant gut microbiota

13 October 2015

Infants of Canadian women who received antibiotics during labour or delivery were more likely to have an altered gut microbiome, according to new research from the Canadian Healthy Infant Longitudinal Development (CHILD) Study.

The study, published in BJOG: An International Journal of Obstetrics and Gynaecology, found that antibiotics used during delivery—whether caesarean or vaginal—were associated with changes in infant gut bacteria at three months of age, and that breastfeeding modified some of these effects when infants were 12 months old.

“Antibiotics are commonly administered to mothers during birth to help protect infants from Group B Streptococcus (GBS) infection,” says the study’s senior author, Dr. Anita Kozyrskyj, an AllerGen investigator and professor in the Department of Pediatrics at the University of Alberta.

“In North America, prophylactic antibiotics are given to all women with a positive vaginal culture for GBS, while some European countries base antibiotic treatment decisions on other risk factors. Our research provides evidence that exposing newborns to antibiotics disrupts their initial gut colonization at a critical time when a baby’s immune system is being established.”

The researchers collected data from 198 children participating in the CHILD Study. DNA sequencing techniques performed in the laboratories of James Scott, a co-Principal Investigator, and David Guttman at the University of Toronto provided information on the types and quantity of bacteria present in the infants’ stool. Information on maternal exposure to antibiotics and mode of delivery were obtained from hospital records, and breastfeeding was reported by mothers.

A total of 43% of mothers received prophylactic antibiotics for GBS during delivery—21% during vaginal delivery; 13% during emergency caesarean-section; and 9% during elective caesareansection—while 57% had a vaginal delivery with no antibiotics.

At three months of age, infants born to women who received antibiotics during delivery had significant alterations in their microbiota, including a lower abundance of Bacteroidaceae and higher abundance of Clostridiales compared to infants whose mothers did not receive antibiotics. These differences persisted at 12 months of age among infants who were not exclusively breastfed for at least the first three months of life.

“Our findings provide new evidence that breastfeeding can modify antibiotic-induced microbiota changes,” says Dr. Meghan Azad, lead author of the study, research scientist at the Children’s Hospital Research Institute of Manitoba, and an AllerGen investigator.

“Eventually, we hope to determine whether these antibiotic-induced changes in microbiota are associated with the development of obesity or allergic disease in children. We also plan to further explore how breastfeeding can minimize the adverse effects of antibiotic use, since there are times when it cannot be avoided.”

This research was supported by the Canadian Institutes of Health Research (CIHR).

The CHILD Study, funded by AllerGen NCE and the Canadian Institutes of Health Research (CIHR), involves more than 3,500 infants and their families from across Canada who are being closely monitored to determine how genetic and home environment factors contribute to health outcomes, especially with regard to allergies and asthma.

Zulyniak MA, de Souza RJ, Shaikh M for the NutriGen Alliance investigators, et al Does the impact of a plant-based diet during pregnancy on birth weight differ by ethnicity? A dietary pattern analysis from a prospective Canadian birth cohort alliance BMJ Open 2017;7:e017753. doi: 10.1136/bmjopen-2017-017753

Kamal M, Tamana SK, Smithson L, Ding L, Lau A, Chikuma J, et al. Phenotypes of sleep-disordered breathing symptoms to two years of age based on age of onset and duration of symptoms. Sleep Medicine. 48:93–100.

Citation

Forbes JD, Azad MB, Vehling L, Tun HM, Konya TB, Guttman DS, et al. Association of Exposure to Formula in the Hospital and Subsequent Infant Feeding Practices With Gut Microbiota and Risk of Overweight in the First Year of Life. JAMA Pediatr. Published online June 4, 2018. doi:10.1001/jamapediatrics.2018.116

Information must be provided on funding mechanisms for sample analyses and the study completion

Evidence must be provided that ethics approval is available

Rationale must be provided as to why the requested samples are required at the current time, rather than after completion of the Study’s 5-year follow-up, with the potential at that time for a more efficient study design; e.g., nested case-controls, etc.